Herbal

Horny Goat Weed (Epimedium)

Also known as: Epimedium, Yin yang huo, Icariin, Barrenwort

Evidence

Traditional Chinese herb with PDE5 inhibiting properties, though weaker than pharmaceuticals.

Primary uses

Libido
Erectile support (mild)
Traditional aphrodisiac

How it works

Contains icariin (weak PDE5 inhibitor)
Traditional aphrodisiac
May support testosterone (weak)
Bone health effects too

Dosage

Typical range: 250-1000mg extract (standardized to 10-20% icariin)
Timing: 1-2 hours before activity or divided daily
With food: Either way
Duration: Daily use for ongoing effect
Special populations: Those seeking mild erectile/libido support

Forms

Standardized to icariin
Traditional extract

Safety

Common side effects

Dizziness
Dry mouth
Nosebleed
Rapid heart rate

Contraindications

Heart conditions
Blood pressure issues
Bleeding disorders

Evidence notes

Traditional use, icariin has PDE5 effects but weaker than Viagra

Grade C: Mostly observational or small trials; mechanism is plausible but unproven at scale.

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Medical disclaimer. This page is educational and does not replace advice from a qualified healthcare provider.